HISTORIC TRUSS BRIDGE REPLACED, RELOCATED TO LAZY BROOK PARK

Author:

MIKE LAUER

Marketing Communications Specialist | Philadelphia, PA

The historic Pierceville Bridge is a particularly unusual and rare type of wrought iron truss bridge called a lenticular truss bridge, so-called because the trusses have a distinctive “lens” shape to them. Originally designed and constructed by the East Berlin Iron Bridge Company in 1881, the bridge previously carried SR 1029 over Tunkhannock Creek in Nicholson Township, Wyoming County, PA. The bridge was closed in 2005 due to structural deficiencies stemming largely from vehicular impact damage and gross deterioration of the floor system.

One of only four lenticular truss bridges still in existence in Pennsylvania, the bridge is also noteworthy because it is the oldest lenticular truss bridge in Pennsylvania and one of the oldest lenticular truss bridges in the United States.

Weighing 50,000 pounds, the 113-foot-long bridge was restored to near-original condition and relocated six miles downstream to the nearby Lazy Brook Park. The bridge is now open to primarily serve pedestrian traffic and has a six-ton emergency vehicle rating. In the current setting, the goal is for this truss to continue to serve as a testament to the engineering accomplishments and craftsmanship of the early 1880s.

The bridge’s rehabilitation included taking it apart, cleaning it, repainting it, and repairing damage it sustained. An “in-kind” type of restoration was conducted rather than a rehabilitation, which focused on making the historic truss look exactly like it did 134 years ago when it was brand new. A key component to this restoration was the use of hot driven rivets in lieu of bolts for the fabrication of all replacement components and repairs that were assembled in the shop.

A new 172-foot-long, two-span prestressed concrete box beam bridge with integral abutments was designed for the replacement structure. The new bridge is open to traffic and has reestablished a secure connection of SR 1029 over Tunkhannock Creek.

McCormick Taylor provided engineering services for the relocation and restoration of the historic bridge, including clearances to relocate the highly historically significant truss bridge to a township park. During construction, we provided engineering reviews and consultation of detail demolition and erection plans, and ensured shop drawings and repair activities were in compliance with both the structural design and maintained historic integrity.

At Lazy Brook Park, the historic bridge crosses a flood relief channel and functions as a footbridge for park visitors. This project provides a new functional bridge for SR 1029 motorists, an iconic landmark for Lazy Brook Park, and preserves one of the rarest historic bridges in Pennsylvania. To complete the look of the bridge at its new location, the stones from the masonry abutments at the original bridge site were moved and incorporated into the new abutments at Lazy Brook Park. An information kiosk was installed at the park to inform park visitors of the bridge’s history and significance.